Fast food and convenience food services are a large industry that is continuing to grow in response to increasing demand for provision of food to large numbers of people in shorter and shorter service times. With the high costs of store space and labor, it is very desirable to have automated food vending systems which are reliable in operation and can provide customers a wide range of choices in types of food. Such vending systems can also expand the reach of the fast food industry into locations which are less suitable for standard retail store franchises, such as in company cafeterias, schools, hospitals, airports, gas and roadside stations, hotels and motels.
Some major disadvantages with conventional automated food vending systems have been the lack of an efficient capability to provide hot foods, and the high costs of current machinery for selling fresh foods or freshly-cooked foods. Current vending machines for fresh foods typically have a large enclosed frame, rotating carousel(s) to display the foods to the customers, and a large door or number of doors to allow access to the selected foods. The machinery is therefore mechanically complex and costly, requires a large amount of floor space, can hold only limited capacities of food units, and requires frequent maintenance and reloading. In order to keep the food from spoilage, conventional vending machines are limited to cold foods or snack foods which may contain high levels of preservatives or which may be unappealing to a wide range of customers. The foods obtained from vending machines can be cooked in a microwave oven installed in the vending area, but the provision of cooking facilities takes up additional floor space and requires frequent cleaning. Also, customers often lack the time or knowledge to operate a microwave oven for optimal cooking results.
Some proposals have been made for vending machines which are less costly, can hold larger numbers of food units, and have mechanisms for delivery to an attached microwave oven. For example, U.S. Pat. No. 4,771,913 to Johndrow et al. discloses a vending machine having stacks of food packages and a dispenser mechanism which dispenses a package vertically downward into a microwave oven section that is accessed through a pivoting gate. U.S. Pat. Nos. 3,333,666 and 3,386,550 to Murray et al., U.S. Pat. No. 3,482,509 to Gardner, U.S. Pat. No. 4,349,714 to Tamano, U.S. Pat. No. 4,398,651 to Kumpfer, U.S. Pat. No. 4,592,485 to Anderson et al., and U.S. Pat. No. 4,677,278 to Knoll show other combinations of microwave cookers and vending machines.
However, the proposed machines have used specially designed and relatively complex mechanisms for dispensing the food packages and/or delivering them to the associated microwave ovens. Machines having a fairly complex delivery path are subject to high rates of jamming and mechanical breakdown. It would be highly desirable to employ a food vending structure which is very simple and reliable in operation and which can be retrofit or installed in existing types of vending machines which have proven delivery mechanisms.
It would also be desirable to provide a capability for automatically cooking the vended food at different temperatures, cooking cycles, or time periods. Some prior proposals have been made for selective control of a microwave oven using preprogrammed bar codes. For example, U.S. Pat. No. 4,323,773 to Carpenter and U.S. Pat. No. 4,780,588 to Edamura disclose microwave ovens having an attached wand or scanner for scanning printed bar codes or a plug-in program unit. However, these systems require preprogramming of the microwave oven control or frequent reprogramming if the types of foods are to be changed. Also, if the customer is required to manipulate of the bar code input for the microwave oven control, there is a risk of an unacceptably high level of incorrect operation and inconvenience to the customer. Therefore, it is desirable to have microwave cooking facilities for vended foods which require a minimum of intervention from customers.